Lamp with decorative element when illuminated

Abstract

A lamp apparatus includes a pair of concentrically positioned lamp shades and a light source positioned centrally within an inner one of the lamp shades. The lamp shades are bell shaped so as to direct light from the light source downwardly without passing through either one of the lamp shades. The outer one of the lamp shades is formed of a transparent glass or plastic with a thin film optical coating of randomly variable thickness on its inner surface. The inner one of the lamp shades is formed of a translucent glass or plastic. Standard lamp hardware is used to assembly the apparatus into a functional lamp assembly. When the light source is not illuminated, the outer shade appears as a metallic or chrome color, and when it is illuminated, the outer shade appears transparent and the inner shade appears to have a rainbow colored effect. Downward directed light is not colored.

What is claimed is:  
     
       1. A lamp apparatus comprising: a pair of concentrically positioned lamp shades and a light source positioned centrally within an inner one of the lamp shades, the lamp shades configured for directing light from the light source downwardly without passing through either one of the lamp shades; an outer one of the lamp shades formed of a transparent rigid material with a non-uniformly thick thin film optical coating of randomly variable thickness thereon; the inner one of the lamp shades formed of a translucent rigid material; and a lamp hardware engaged with the lamp shades and light source for maintaining fixed mutual positions thereof. 
     
     
       2. The apparatus of  claim 1  wherein the thin film optical coating is applied to an in-facing surface of the outer one of the lamp shades. 
     
     
       3. The apparatus of  claim 1  wherein the lamp shades are made of one of glass and plastic. 
     
     
       4. The apparatus of  claim 1  wherein the lamp shades are bell shaped. 
     
     
       5. The apparatus of  claim 1  wherein the inner one of the lamp shades is comprised of two individual shade portions integrally abutted. 
     
     
       6. The apparatus of  claim 5  wherein the two individual shade portions are comprised of materials having different indexes of refraction. 
     
     
       7. The apparatus of  claim 1  wherein the thin film optical coating comprises plural layers of optical materials. 
     
     
       8. The apparatus of  claim 7  wherein the optical materials are oxides. 
     
     
       9. The apparatus of  claim 8  wherein the oxides include titanium dioxide and silicon oxide. 
     
     
       10. The apparatus of  claim 1  wherein the thin film optical coating is deposited using flash evaporation of optical compounds. 
     
     
       11. The apparatus of  claim 1  wherein the thin film optical coating is deposited using physical sputtering of optical compounds.